It is known to form a cross-sectional profile of a tubular member by a hydro-forming process in which a fluid filled tubular blank is placed within a cavity of a die and then the die is closed so that the tubular blank is enclosed within the die. Fluid pressure is then increased inside the tubular member to expand the blank outwardly against the cavity of the die to provide a tubular product having a die formed cross-sectional profile.
During tube hydroforming, punches of various shapes and sizes are used to create necessary openings in the tubular member. Hydraulic cylinders activate the motion of the punches. A solid mechanical mounting between the punch and a cylinder rod is necessary in order to provide the required strength needed for the piercing operation.
As the request for hydroformed tube applications grows, the need for higher number of opening or hole piercing also increases. Tubular members are not only designed with more openings, but the production number of parts is constantly increasing. As a result, punch resharpening and the time needed to replace dull punches in the die are becoming more important. However, the methods currently used to replace a punch in the die, requires the dismount of the hydraulic cylinder and/or the dismount of die inserts in the area of the punch needing replacement. This operation will also require the disconnection of hydraulic lines and, in most cases, the die will have to be outside of the press. The procedure is highly time consuming and is effecting production in a very negative way.
As a result, it is desirable to provide quick change of hydroforming punches during the hydroforming piercing process. It is also desirable to provide a less time consuming way of changing punches during the hydroforming piercing process. It is further desirable to change punches in a hydroforming die during piercing process. Therefore, there is a need in the art to provide a new quick change assembly for a hydroforming punch that meets these desires.